Kevin C. Walsh, an assistant professor of law at the University of Richmond School of Law, said the Wickard decision became the high-water mark of Congress' reach under the Commerce Clause.

"After Wickard was decided, it was thought for at least the next 50 years there was nothing outside the reach of Congress' power," Walsh said..

Not surprisingly, Paul D. Clement, a lawyer who is challenging the health care law on behalf of 26 Republican governors and attorneys general, sees Wickard in a different light than his opponents.

The Supreme Court decided to devote a whopping 5 1/2 hours of arguments to the health care case.
"That's an awful lot of time for a case that is squarely covered by Wickard," Clement said wryly at a recent talk sponsored by Georgetown University School of Law.

In court briefs, Clement has distinguished his case from Wickard by arguing that Filburn was already in the marketplace as a wheat farmer. He said in Wickard, Congress was allowed to regulate "a single farmer's apparently de minimis production of a nationally marketed commodity. But it would not justify a law requiring others to produce or purchase that commodity."

Two judges on the 11th Circuit Court of Appeals who voted to strike down the law agreed with Clement.

"Wickard is striking not for its similarity to our present case, but in how different it is," Judges Joel F. Dubina and Frank M. Hull wrote.

The judges reasoned that Filburn was already a commercial farmer, thus in the marketplace, and that Congress left him with choices.

"He could have decided to make do with the amount of wheat he was allowed to grow. He could have redirected his efforts to agricultural endeavors that required less wheat. He could have even ceased part of his farming operations."

The judges said that regulation imposed by Congress was a limitation, not a mandate similar to the individual mandate in the health care law.

To make the distinction crystal clear, the judges wrote, "Individuals subjected to this economic mandate [in the health care law] have not made a voluntary choice to enter the stream of commerce, but instead are having that choice imposed upon them by the federal government."

Both sides of the issue will try to use Wickard in the best light.

"The government says when you look at the aggregate economic cost of the people who choose not to buy health insurance but later seek health care, it substantially affects interstate commerce," Walsh said. "On the other hand, opponents will say that Wickard involved the regulation of someone who was already engaged in interstate commerce by virtue of his farming operation."

There are certainly other cases regarding the role of Congress that will be heavily relied upon by both sides of the case, but perhaps no others where the extent to which the facts resemble the health care litigation will be so thoroughly contested.

James Chen, dean and professor of law at the University of Louisville, said Wickard will stand out because it "captures the imagination of the American public."

"We imagine farming to be the one profession anyone can do without interference. Filburn was a small family farmer in what is now suburban Dayton, Ohio. His story -- more than the other commerce clause cases involved here -- will resonate with the American public. "